ISO 3890-2:2009

Overview

ISO 3890-2:2009 (IDF 75-2:2009) is the international test-method standard for purification and confirmation of organochlorine pesticide residues in milk and milk products. As Part 2 of the ISO 3890 series, it complements ISO 3890-1 by specifying chromatographic clean-up procedures, liquid–liquid partitioning options and confirmatory tests following extraction. The standard is the second edition (2009) and is published jointly by ISO and IDF.

Key topics and technical requirements

• Defines multiple validated clean-up and partitioning procedures (Methods A–H), including:
  • Liquid–liquid partitioning (e.g., acetonitrile or dimethylformamide (DMF) partitioning)
  • Column chromatography on adsorbents such as Florisil, alumina, silica gel (partially deactivated), and aluminium oxide of defined activity
  • Gel-permeation chromatography (GPC) for matrix separation
• Specifies reagents and apparatus requirements (solvent grades, adsorbent activation, column dimensions, rotary evaporators, separating funnels)
• Describes method-specific eluents and eluate fractions for separating groups of organochlorines (for example, separation of HCH isomers, heptachlor/heptachlor epoxide, aldrin/dieldrin/endrin)
• Includes confirmatory tests and additional clean‑up procedures to verify identity and reduce matrix interferences prior to instrumental analysis
• Requires final examination by gas chromatography (GLC/GC) and references analytical quality checks for adsorbent batches and solvent purity
• Contains specific adaptations for different dairy matrices (milk, butter, cheese)

Practical applications

• Standardizes laboratory workflows for reliable detection and confirmation of organochlorine pesticide residues in dairy products
• Helps laboratories meet regulatory monitoring requirements and enforce food safety limits
• Improves analytical reproducibility by prescribing clean‑up, fractionation and confirmation steps that reduce matrix effects and false positives
• Useful in method development, validation, inter-laboratory studies and proficiency testing for pesticide residue analysis

Who should use this standard

• Food safety and public health laboratories
• Dairy industry quality control and product testing labs
• Regulatory authorities and inspection agencies
• Analytical chemists developing or validating pesticide residue methods
• Accredited testing laboratories preparing method SOPs and compliance reports

Related standards

• ISO 3890-1:2009 | IDF 75-1:2009 - General considerations and extraction methods (complements Part 2)
• Other national and international pesticide residue method standards and laboratory accreditation guidance

Note: ISO 3890-2:2009 involves hazardous solvents and operations; the standard includes a safety warning and users must follow appropriate health, safety and regulatory requirements.